


Spirits of Steel

by DeterminationIsNotCrash



Category: Undertale (Video Game), スーパーロボット大戦 | Super Robot Wars
Genre: Alternate Universe - Gaster Blaster (Undertale), Breaking Through Fate sidestory, Gaster Blaster Papyrus (Undertale), Gaster Blaster Sans (Undertale), Gen, Not to be taken seriously, The Absolute God of Hyperdeath (Undertale), mecha references
Language: English
Status: Completed
Published: 2018-10-19
Updated: 2018-10-19
Packaged: 2019-08-04 07:47:36
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,269
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16342712
Author URL: https://archiveofourown.org/users/DeterminationIsNotCrash/pseuds/DeterminationIsNotCrash
Summary: The despair and anguish of one whose SOUL was dragged down by gravity.The limitless light of the seven whose SOULs were determined to overcome gravity.In this clash between an unstoppable force and an immovable object, who would rise, and who would fall?For Gasterblastober.





	Spirits of Steel

**Author's Note:**

> Song I got the title (and general atmosphere of the fic) from: https://www.youtube.com/watch?v=BiOsx0zJ2Mk

The entire world was ending. An enormous meteor enveloped by purple flames loomed over Earth. It had already devoured the other planets of the Milky Way and added them to its mass. The puny blue planet before it would vanish completely, billions of lives snuffed out as easily as a flame on a candle.

And yet, within the meteor, there were the souls of seven passionate heroes. Seven people who were fighting with all their might for the sake of their home. Even if the master of the meteor tried to choke them in darkness and despair, their golden spirits were determined to outshine it!

A bulky steel mech punched through another wave of enemies, its glowing golden fists carving a bright path through the shadows. “ ** _WINGDIIIINGS!_** ”

“Papyrus! Do you really believe a forgettable, worthless monster like you can stop the noble ambitions of I, Wingdings!?”

“Nothing’s noble about dropping a meteor on Earth! You’re committing genocide, and for what!? In case you don’t remember, wasn’t your goal to _save_ monsterkind!?”

The AI-controlled robots continued to stream forth, creating an insurmountable barrier between Papyrus and Wingdings. “My goal always was, and still is, just. All I want is to escape the cursed prison of gravity… of fate! If destroying Earth is the only way for the SOULs of the people to be no longer dragged down by gravity, so be it! Death is preferable to a life of bowing down to those in power!”

“You’d rather destroy everything than not have things your way…!? You’re completely insane!” A Boost Knuckle tore through several more robots! But the moment the enemies were taken down, more arrived to take their place! No matter how powerful or skilled a fighter was, sheer numbers could still overwhelm them!

The pilot cursed under his breath. He was going to be shot down before he even _reached_ Wingdings!

But many miracles existed in this world. In reality, miracles weren’t created by coincidence or fate, but by resolute hearts which were so powerful, onlookers had no other choice than to rationalise their logic-defying feats as ‘miraculous’! One of these miracles took the form of a rain of lasers that blew all the enemy robots back!

Papyrus couldn’t help but smile when he saw the source of the lasers – a dozen familiar drones hovering in mid-air. “Sans…!”

A powerful roar reverberated throughout the hall. **_“FIN FUNNELS!”_** With grace and coordination, the drones spread out. Although the individual beams were small, the lasers packed enough punch to pierce the enemies’ armour.

A white suit with a distinctive V-fin rushed to the skeleton’s side. It was smaller and sleeker than Papyrus’ armour of choice. It didn’t have as much raw power, but speed was its domain.

Papyrus’ video communication channel opened, revealing the panting dragon-like pilot. “I swear, this place is a maze… Sorry for the wait, bro! Did I _meikyuu_ worry?”

The younger skeleton restrained the knee-jerk reflex to whack his brother. Just like the pilot, Sans’ mech was a lot more fragile than Papyrus’. “It’s fine, you’re just in time. Splitting up might not have been the best decision, though…”

“Don’t worry, Al and the others are on their way! But there won’t be a need to wait any longer… Because the two of us are more than enough to take down this overgrown lizard!” The mobile suit handed an energy pack and repair kit to the super robot. “Sit back and refuel your weapons with this. By the time you’re done, these hunks of junk’ll be scrap metal!”

Sans drew his weapons and charged! The lumbering messes of metal that Wingdings’ factory welded together at last minute couldn’t even touch Sans. To the focused ace pilot, it was as if the enemies were moving in slow motion – his suit didn’t even get a scratch, and with the robots left open, he could easily counter with a slash from his sword or shot from his gun.

However… the number of robots in the way weren’t decreasing. In fact, they were still multiplying! Sans’ mobile suit was being pushed back…!

True, Sans could evade the enemies’ attacks with ease… but he wasn’t dealing enough damage to take a single one down. By sacrificing heavy weaponry and armour for speed, Sans lacked the firepower to incapacitate the enemies. His ultimate attack, the Fin Funnels, could puncture the enemies’ armour, but that was the best thing he had! It would take _all_ of the Funnels and _all_ of Sans’ focus to take down _one_ of Wingdings’ grunts, and the Blaster-headed skeleton couldn’t do that while dodging.

Sweat starting to drip from his forehead, Sans glanced back at the still-refuelling super robot. _Damn it… I wanted to impress Papyrus, for once…!_

As the skeleton was seriously regretting the words that just left his muzzle, the promised reinforcements arrived. **_“Busterrrr… Tomahawwwk! NGAAAHHHHHHH!!”_** Two pure white arcs cleaved through the enemies surrounding Sans. The two massive axes were wielded by a steel giant that dwarfed both of the skeleton brothers!

Papyrus and Sans could hear the pilot’s cocky grin over the comm channel. “Hey, hey, don’t leave us out of the fun!” Undyne and Alphys had arrived!

The massive silver warrior sized up Wingdings’ cold gaze from the end of the hallway, alongside the endlessly spawning horde of machines between them. “Looks like we arrived in the nick of time… right, Alphys?”

“I-it looks like it…”

Undyne glanced at the fully recovered Papyrus… then at Wingdings, hiding behind his robot army. “Al… are you thinking what I’m thinking?”

“I-I mean… probably???”

“ _Great_! Let’s do this! **_RAHHHHHHHH!_** ” With a mighty battle cry, the robot soared into the air, its head nearly bumping the ceiling. Then… it set on fire! The giant kick it unleashed struck like lightning… Super lightning! The flaming meteor surged through the enemies before them, parting the ocean of metal. Finally, there was a clear path to Wingdings!

“Now, Papyrus! Go! You’re the one who has things to settle with Wingdings!”

“Right! Change! Wing Gust!” The form of Papyrus’ super robot changed and twisted, transforming into a shape reminiscent of a bird. Its now-airborne form accelerated towards its enemy.

But Wingdings’ servants wouldn’t allow that! Multiple grunts rushed inwards, quickly starting to fill the gap.

“No, you don't!” A group of Fin Funnels blocked their way and fired at them. The robots changed their target to Sans, but the several pincers and lasers were blocked by a heavy steel arm.

“Sans, draw their fire! We’ll take them out while you have them distracted!”

“Great ideas as always, Al!”

Thanks to the efforts and faith of his friends, Papyrus could finally reach Wingdings. He changed his robot back to its humanoid mode, then took a fighting stance.

“Very well, Papyrus… I will settle everything with you. The errors of my past… no, the errors of the entire world… I shall correct them all!” The horned red mobile suit Wingdings was piloting rose from its throne. It raised an arm, and the floor that they were standing on plummeted into the inner depths of the meteor!

 _The whole thing was a hidden platform!?_ Papyrus had to dig his claws into the controls to prevent himself from hitting the ceiling of the cockpit. With a heavy thud, the platform crashed into its destination.

They had arrived at a large spherical chamber, walls decorated by depictions of humans being bloodily ripped apart. Among them was also a yellow flower, torn to shreds by several skeletal limbs. A towering draconic figure hovered over the sea of fire, blood, and guts, like a wrathful deity descending from the sky. The interior of the meteor changed depending on its master… so it was only natural that the innermost chamber of the meteor would display Wingdings’ true feelings!

Papyrus couldn’t see Wingdings over the comm channel, but he could _feel_ the oppressive aura he exerted. In fact, the entire core of the meteor seemed to be filled with this soul-crushing atmosphere. “A fitting stage for the final round, don’t you agree? This place will be your tomb!”

“No, Wingdings. _You’re_ the one who will die tonight! Drown in your own hatred!” Papyrus lifted his mech’s hand into the air. “Two stars of calamity shine bright in the heavens… Calamity Sword!” From out of nowhere, a lightning bolt struck the super robot’s hand, materialising into a heavenly, sacred blade. Despite its foreboding name, it had the power to hold back the night and banish all evil… perfect for cutting apart the unholy abomination that Papyrus’ father had become!

The horned skeleton rushed at Wingdings, his blade at the ready… but ran straight into a barrage of lasers!

“Fool! Do you really believe I didn’t know about your ‘sacred blade’? I know that one touch means instant death for me, so I refuse to let that _thing_ even come close!” The red suit hovered back to the wall of the chamber, five Funnels coming to life and swarming their target. “Your main method of attack is melee… so if I stand back, I can just shoot you to death.”

Before the Funnels could hit, Papyrus quickly changed his robot back into its aerial form and swerved out of the way. _In this form, I also have access to…!_ From within the wings, several missiles burst out and soared towards Wingdings!

The pilot could hear Wingdings let out a grunt of surprise, but that was all the attack produced. Four Funnels raced back to their master into a formation around him, forming a barrier which blocked every single one of the projectiles.

Papyrus’ spikes suddenly stood on end. _!?_ Thanks to his part-Blaster nature, he had the senses to detect an attack coming from behind and the reflexes to dodge. Unfortunately, his robot was a different story. “Tch…!” The single stray Funnel managed to land a hit on his energy generator. With his finite resources, he was already running on borrowed time, but now said time was quartered!

The horned skeleton glared at Wingdings, his eyes glowing with contempt. “You coward.”

“Whatever it takes to win.” The Funnel started to fly back towards the mono-eye mobile suit, but Papyrus fried it with an Omega Laser.

The skeleton took a deep breath, then analysed the situation before him. The demon dragon’s Funnels were commencing their next attack, so he only had three seconds max to strategize. Wingdings might _seem_ invincible, but he was extremely reliant on those Funnels of his for both attack and defence. Therefore…!

“If you’re willing to do whatever it takes to win, then I’ll respond in kind!” The bird-like robot gained a golden aura as it started to spin around like a drill! **_“SPIRAL ATTACK!”_** With the extra mobility and speed gained from its shape, it swiftly closed the distance between itself and Wingdings’ mobile suit. On top of that, he launched every single missile he had left!

But this was the problem: the demon dragon still saw it coming. The drill scraped his suit, but did no significant damage as Wingdings slid out of its path. Once again, his Funnels formed a barrier and blocked the projectiles.

Papyrus grit his teeth. He only had one shot to do this…! He shifted back into humanoid mode and slashed wildly at the Funnels! The golden sword managed to destroy two of the laser drones before the robot hit the ground. The remaining two immediately rapidfired at the super robot, blowing open several holes in its armour. The pilot’s chest tightened as one of the lasers blew off his mech’s right arm… and with it, the Calamity Sword.

“ ** _BOOST KNUCKLE!_** ” Papyrus smashed both remaining funnels with his other arm, but not before they blew off his robot’s face. “Dammit…! I’m not dead yet! That was just the main camera!”

His robot’s arms were too damaged to return, and naturally, that also made using his sword out of the question. All of his weapons in humanoid form were inoperable! And to make matters even worse, he was nearly out of energy!

Wingdings landed and casually strolled towards Papyrus, drawing a laser sword. “As expected, you wasted all your energy taking down my Funnels… Now you’re a sitting duck.”

The communication module was damaged, so Wingdings couldn’t see or hear what was going on inside that cockpit of steel. The demon dragon expected his son to be drowning in despair, praying that at least his death would be a painless one. Little did he expect Papyrus’ expression to be one of complete focus. _Strike… Alert… Soul… Fury…_

“My former favourite son, who was foolish enough to defy me! I bid you farewell!” Just before the beam sword came down, the mech changed into its Wing Gust mode! **_“WHAAAAT!?”_** Was the boy insane!? His robot was barely keeping together, and its generator was starting to spark! If he tried to do _anything_ , it would either fall apart or explode!

“My final… ** _SPIRAL ATTAAAAAACK!_** ” Wingdings was too close to dodge! The point-blank drill attack rammed into the villain’s suit and tore through the cockpit!

**_“GYAAAAAAAAAAHHHH!”_ **

The horned skeleton ejected from his own cockpit, the boost from his Blue Attack allowing him to escape the explosion with minimal injury. He hit the ground with a thud, gasping for breath. “I was a sitting duck? Well, maybe _you_ should have _ducked_.” He held back a tear as he saw what was left of his super robot disappear in flames. “Goodbye, partner. Thanks for everything.”

A chill ran down Papyrus’ spine. His tail curled around his legs of its own accord. “Odd… I thought defeating Wingdings would have dispelled the atmosphere… and shouldn’t the meteor have stopped by now!?”

**_“That’s because I didn’t die.”_ **

The guttural, demonic rumble that shook the very air… made Papyrus seize up.

 ** _“Impressive… You’ve done well in defeating my robot… However. This is no mere mobile suit.”_** The wreckage of the destroyed suit started to twist and pulsate, grotesque cracks and snaps echoing throughout the chamber. The metallic sheen of the Gundarium Alloy vanished, taking on an organic and horrifyingly familiar texture… bone.

“T-the failed weapon from earlier!?” No, it wasn’t the bone dragon from Wingdings’ labs. This one was far, far more vicious and otherworldly. Just looking at it made Papyrus fall to his knees. “I-it couldn’t be…”

The corners of the demon’s mouth curved upward. **_“Denial will get you nowhere! This_ is _the Apocalypse Cannon!”_**

All Papyrus could do was stare up at his doom, his eye sockets glazed over. The great beast’s jaws swung open, an energy attack starting to gather. _I’m… done for._

 **“ _Dead End Shoooooot!_ ” **From above, two laser beams pierced the dragon! The Apocalypse Cannon’s own attack dispersed as it howled in pain!

Three shapes dropped down into the chamber, descending from above like guardian angels. Papyrus’ eyes lit up at the sight. “Asriel! Frisk! Gaster!”

The sniper gave a thumbs up. “This makes us even for what I did in the past timelines.”

Papyrus chuckled. “In fact, now I’m in _your_ debt… I’ll treat you to another delicious meal once this is over with!”

“Only if I get to decide what recipe you use!”

“Deal.”

The bulky blue tank of a robot piloted by Papyrus’ quadrupedal friend lumbered over to the skeleton. Strapped to it was…!! “Papyrus, this is for you!”

“The new machine was finally completed… Much appreciated, Gaster!”

Gaster removed the mech from his back, then helped Papyrus climb into the cockpit. It was significantly smaller than a super robot, roughly the same size as Sans’ mobile suit… but packed within its compact frame was an amazing secret weapon.

“Everything good with the new suit, Papyrus? I’d appreciate it if you hurried up!” The slender airborne mech Frisk was piloting maneuvered around the Apocalypse Cannon, drawing its fire. He could avoid the bone attacks and laser blasts for now, but they were all way too close for comfort!

“Right, I’m ready! **_Variable Formation, goooooo!_** ”

The machines Papyrus, Gaster, and Frisk were piloting changed shape! Not into a plane, like Papyrus’ old robot. Not into an animalistic shape, like Sans or Gaster. They became _parts_! Parts that flew together, assembling into a brilliant, imposing figure. Alone, the robots were formidable weapons. Together, nothing could stop them! The Invincible Super Robot had formed!

Wingdings growled, the Apocalypse Cannon mirroring his vocalisation. **_“You really believe that walking toy advertisement can even scratch the mighty Apocalypse Cannon, my entire life’s work, the vessel of my justice!? You fools shall pay for even_ thinking _such blasphemy!”_**

This time uninterrupted, the jaws of the dragon opened wide. A terrible violet light began to gather within.

Papyrus looked down at Asriel, then at the images of his friends on the monitors beside him. “Everyone, let’s go! Time to make some fried Blaster!”

A unanimous, passionate “YEAH!” echoed from the other three cockpits.

“T-Link, Twin Contact! Metal Destroyer mode activated!” Frisk and Asriel reported. The God of Hyperdeath’s mech transformed into a massive cannon, comfortably fitting into the combined super robot’s hand.

“ ** _TRONIUM ENGINE, FULL DRIVE!_** ” Gaster roared, the sudden change in demeanour reminding everyone of how terrifying Blaster beasts could be.

Papyrus grinned. _The machines and pilots are all synchronised perfectly! We just might make it…!_ **_“THE ULTIMATE MOVE! HEAR THE ROAR! OF THE H! T! B! CANNOOOOOOOON!”_** Wonderous golden energy burst from the cannon. It formed into the shape of a majestic, awe-inspiring bird, its powerful wings able to withstand all adversity and soar towards a bright future!

The Apocalypse Cannon let out a massive energy beam of its own! **_“SURGING DRAGON FAAAAAANG!”_** This one was shaped like a vicious, ravenous leviathan, a serpentine monstrosity ready to devour and consume all in its path.

The brilliant, planet-destroying attacks raced towards each other! The two equally powerful forces, one filled with hope and light, the other filled with hatred and despair, collided! From the point of contact, a blinding light streamed forth, flooding not just the meteor, but the entire universe with white!

* * *

Sans was vaguely aware that he was chewing on plastic model kit parts. When he swallowed, causing the parts to clog his throat, he snapped wide awake.

“ _Pleh!_ W-what the!? Where’s the Apocalypse Cannon? Where’s Papyrus and the others? Where’s the SR-”

As he got up from the desk, he noticed headphones clatter off his skull. He checked the screen on the laptop they were attached to. “…‘Alphys’ sugoi kakkoii playlist’…” That settled it – that was the last time he would fall asleep while listening to music his best friend recommended!

Briefly disoriented by the unfamiliar surroundings, he surveyed the area. The environment he was surrounded by didn’t help matters either…

 _Ah, now I remember…_ He was really impressed by the quality Gunpla collection Papyrus amassed, and wanted to build models just like his. That explained why he fell asleep in his brother’s room – Papyrus let him use his robot figures as a reference while he and Alphys worked on another project.

He grimaced at the parts he was supposed to be building, which looked like they had been chewed up by a dog. It didn’t look like it helped much, unfortunately…

He shrugged and discarded the ruined kit. It didn’t matter much – it was actually just a cheap knockoff version. “Heh, oh well. Guess building cool robots can wait for another day.”

By the time he cleaned up and left for _Grillby’s_ , thoughts of mechs had completely left his head. The short dragon-like skeleton was far more interested in deciding between a burger, pizza, or parmigiana. He didn’t even notice the blue steel behemoth standing beside the garage.


End file.
